O Lord of my soul, who can find words to tell what Thou givest to those who trust in Thee, and how much, on the other hand those lose, who, though they may have attained to ecstasies and rapture, yet confide in themselves! -St. Teresa
This Saint said she had known persons eminent in virtue, and who had even attained to the prayer of union, who afterwards fell into the power of the demon, because of their overweening self-confidence. For, when the soul sees herself so near to God, and perceives the vast difference between the good things of heaven and those of earth, and experiences the great love the Lord manifests for her, there springs up from these favors such security of nevermore falling from the happiness she enjoys, that it seems to her impossible that so delightful a life should ever be exchanged for the baseness of sensual delights. With this confidence, she begins to expose herself to labors and dangers, without discretion or regard to proportion, not considering that she is not yet in condition to leave the nest and fly, as her virtues are not confirmed, and she has no experience of danger.
Text from A Year With the Saints (New York: P.J. Kenedy & Sons, 1891).